The invention relates to an apparatus for protecting persons entering a zone of danger of power-operated textile machines, in particular, of devices for opening bales of spinning fiber material, e.g. cotton, by reducing means, e.g. milling devices, etc.
It is common practice that moving elements, in particular driving units of machinery including textile machines, have been protected against undue approaches of any kind. Since driving elements with movable parts are mounted stationarily, a fixed casing will generally suffice for protection. The casing may be designed, so that the machine is automatically stopped if the casing is opened.
For the control and protection of walkable zones of danger in connection with power-operated textile machines, it is known to mount a transmitter and a receiver in a mutual space. Upon the interruption of a beam path between them by an intruder, a signal is initiated and used for the direct interruption of a possibly dangerous movement of the textile machine. It has been known to provide an interrupter in the form of a light barrier protection. Openers for textile fiber bales comprise moving fiber milling units having more than one zone of danger. The mutual spatial arrangement of transmitters and receivers may be divided to ensure that the zone of danger is completely enclosed by the beam path between transmitter and receiver for corresponding operating positions of the milling units. However, in practice, the subdivision of a light-beam barrier is often impractical. With the set-up of a new bale, the opposite safety barrier is often interrupted unintentionally, with a resultant standstill of the machine. A correction of the bale setup is only possible if the total operation is interrupted. For narrow space conditions, the zones of danger to be protected may be marked, but only with difficulty.
Accordingly, an object of the present invention is to reliably operate a safety sensor for power-operated textile machines and restrict its action to a sphere necessary for protection.